The Vietnamese word "quay lơ" typically means to fall down suddenly, often in a dramatic or unexpected way. It can be used in both literal and figurative contexts, where someone might faint or lose consciousness due to shock, surprise, or other strong emotions.
In more advanced contexts, you might encounter "quay lơ" being used to describe situations that are overwhelming, even if they don't literally involve fainting. For example, "Cảnh tượng quá đẹp khiến tôi quay lơ." (The scene was so beautiful that it made me feel faint.)